1. Field of the invention
The present invention relates to an apparatus for and a method of manufacturing a metal ribbon of an amorphous metal and the like.
2. Description of the Related Art
A single roll method which uses a single cooling roll has come into widest use as a method of manufacturing a metal ribbon. FIG. 24 shows the main portion of an apparatus for embodying the single roll method, wherein a cooling roll 101 is rotated at a high speed and a melt 103 is jetted from a melt nozzle 102, which is located in the vicinity of the apex of the cooling surface of the cooling roll 101, so that the melt 103 is rapidly solidified on the cooling surface of the cooling roll 101 and drawn out in the rotating direction of the cooling roll (toward the direction of an arrow A).
The melt 103 jetted from the melt nozzle 102 forms a staying portion (hereinafter, referred to as a "puddle") 104 between the extreme end of the melt nozzle 102 and the cooling surface of the cooling roll 101. As the cooling roll 101 rotates, the melt 103 is successively drawn out from the puddle 4, rapidly cooled and solidified on the surface of the cooling roll 101 and a ribbon 105 is continuously formed.
When a material used in the single roll method is composed of a component which is liable to be oxidized, the melt nozzle 102 is clogged with the material by the oxidation thereof and the jet of a melt may be prevented by it. To solve the problem, there is conventionally proposed a method of preventing the oxidation of the material by disposing an overall ribbon manufacturing apparatus in a chamber and filling the interior of the chamber with an inert gas to thereby reduce an oxygen concentration in the vicinity of the melt nozzle.
The method of filling the interior of the chamber with the inert gas is very effective to prevent the clogging of the melt nozzle. However, it is defective in workability because the overall apparatus is disposed in the chamber. For example, there is required a troublesome job of opening the chamber each one charge and charging a material to be melted to a melting furnace or a crucible, closing the chamber again and thereafter replacing the atmosphere in the chamber with the inert gas atmosphere. there is also a problem that a large cost is necessary to attendant equipment for maintaining the interior of the chamber to the inert gas atmosphere.